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A FACTOR FROM NORMAL TISSUES INHIBITING TUMOR GROWTH.
1Laboratories of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Embryo skin and placenta extracts significantly inhibit mouse carcinoma growth, with notable retardation in most cases. This anti-tumor effect, observed in over 3800 inoculations, shows promise in cancer research.
Area of Science:
- Oncology
- Biochemistry
- Developmental Biology
Background:
- Transplantable carcinomas and sarcomas in mice are common models for cancer research.
- Placental and embryonic tissues are known to contain biologically active compounds.
- Previous research has explored the anti-proliferative effects of various natural extracts on tumor growth.
Purpose of the Study:
- To investigate the effect of desiccated embryo skin and placenta extracts on the growth of transplantable mouse carcinomas and sarcomas.
- To determine the efficacy of these extracts in suppressing or retarding tumor development.
- To identify the gestational stage of placental extract production that yields maximum inhibitory activity.
Main Methods:
- Preparation and extraction of desiccated embryo skin and placenta.
- Inoculation of tumor cells (carcinomas and sarcomas) into mice, followed by administration of tissue extracts.
- Control groups received tumor cells without extracts.
- Observation and quantification of tumor growth suppression and retardation over time.
- Analysis of placental extracts from different gestational periods in rabbits.
Main Results:
- Desiccated embryo skin and placenta extracts demonstrated a significant retarding effect on the growth of two transplantable mouse carcinomas.
- These extracts were ineffective against mouse sarcomas.
- Complete growth suppression was observed in 55-71% of carcinoma instances treated with extracts, compared to 21-27% in controls.
- Partial growth retardation was noted in nearly all cases where complete suppression did not occur.
- The placental inhibitor was detectable from the second trimester of pregnancy, peaked in the last trimester, and diminished near term.
Conclusions:
- Desiccated embryo skin and placenta extracts possess potent anti-carcinoma properties in mice.
- The inhibitory effect is specific to carcinomas and not observed in sarcomas.
- Placental extracts exhibit stage-dependent inhibitory activity, with maximal effect during late pregnancy.
- These findings suggest the presence of a novel anti-tumor agent in placental and embryonic tissues with potential therapeutic applications.
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